A secret process that requires neither “concrete facts” nor “irrefutable evidence” …

“Instead of a watchlist limited to actual, known terrorists, the government has built a vast system based on the unproven and flawed premise that it can predict if a person will commit a terrorist act in the future,” says Hina Shamsi, the head of the ACLU’s National Security Project. “On that dangerous theory, the government is secretly blacklisting people as suspected terrorists and giving them the impossible task of proving themselves innocent of a threat they haven’t carried out.”

—The Secret Government Rulebook For Labeling You a Terrorist